CITRIS sponsored WAVE ENERGY CONVERTER 2013 UC Davis Mechanical Engineering Alex Beckerman, Kevin Quach, Nick Raymond, Tom Rumble, Teresa Yeh

Contents Introduction Technical Review Construction Next Stage An overview of the CITRIS Renewable Energy Grant proposal, and project’s scope Preliminary Design and Research Technical Review Terminology and main features of our WEC design. Subsystems Buoy Spar PTO Hydraulics Electronics Heave Plate Construction A comparison of the two hydraulic motors regarding power performance, efficiency, and cost. Next Stage Testing in Bodega Bay Instruction Manual

Project Introduction

CITRIS introduction 2012 CITRIS Sustainability Competition Winners $10,000 Renewable Energy Research Grant (+ $5,400 funding for testing) Complete project within one year from award

Objectives introduction 1. Design and fabricate a Wave Energy Converter (WEC) 2. Use standard parts and components to build the PTO 3. Create a set of instructions and share information over website

Preliminary Designs and Research

Preliminary design & Research Potential Test Site: Bodega Bay, Ca Exposed to Pacific ocean waves and wind swell Local university facility to assist with deployment Steep ocean floor topography (bathymerty) Close proximity to UC Davis Team has personal knowledge of area Image: googlemaps.com

Preliminary design & Research Bodega Bay Marine Lab Source: OceanGrafix.com http://www.oceangrafix.com/chart/zoom?chart=18643

Preliminary design & Research Significant Wave Height 1981-2008 NOAA Buoy 46013 NOAA provides ocean data for last 28 years Buoy anchored 14 miles off shore Dominant wave period remains constant Wave height expected to increase closer to shore Dominant Wave Period 1981-2008 KEY

Preliminary design & Research Bond graph Modeling Transfers system from mechanical translational domain to the electrical domain Determines hydraulic damping coefficient for given electrical resistance Damping coefficient used in state space dynamic modeling

Preliminary design & Research State Space Modeling Model to represent the dynamics of our physical system in ocean Linear wave model: approximation of ocean waves as sinusoids. [1] Equations developed within state space using a free body diagram. The system is modeled as a two body system with individual forces acting on each body. MatLab Simulation for Different Heave plate sizes used in Iteration Process Free Body Diagram of Buoy- Heave Plate Dynamics

Preliminary design and research [ WEC_001] [ WEC_002 ] [ WEC_003 ]

Technical Background

PTO Buoy Spar Have Plate [ WEC_004 ] Technical background PTO Buoy Spar 47.3 ft Have Plate [ WEC_004 ]

SUB-SYSTEMS (BUOY)

Buoy

buoy Preliminary testing of foam Fabricated one cubic foot mold out of plywood and wood screws Filled mold with two part expanding polyurethane foam Results From Initial Foam Test

Buoy Lining the mold with plastic to assist with releasing the foam from the mold Positioning the PVC pipes

Buoy Marine grade polyurethane foam Mixture come in two parts, expands when mixed Final volume is 15 times the original volume after 20 minutes of curing

Releasing the foam from the mold Buoy Releasing the foam from the mold

The foam was cut with a chainsaw to form the 45°chamfer Buoy The foam was cut with a chainsaw to form the 45°chamfer

The buoy was then sanded down and coated with a pigmented epoxy resin

Buoy Steel plates mounted on the upper and lower surfaces of the buoy All thread compresses the plates and secures buoy to the spar

SUB-SYSTEMS (SPAR)

spar Hydraulic

spar

spar The bolt holes were drilled on the mill to assist in accurate alignment. Welded components into framework

spar Housing for springs and hydraulic shaft Wire rope alignment housing

SPAR Addition of strut members

SPAR Strut members welded to the spar Secured to the buoy bottom plate

Spring alignment

Alignment brackets 5 spring alignment brackets to keep the 6 springs inline

Alignment brackets Bushing doubles as spring alignment and linear guide for hydraulic rod extension

Alignment brackets Cylinder alignment bracket

SUB-SYSTEMS (POWER TAKE OFF SYSTEM)

Power take-off system

Power take-off system Hydraulic Subsystem elements: Hydraulic Ram Bladder Type Accumulator Piston Type Motor Standard hydraulic hoses and fittings System Operation: Direct drive Reverses direction with each stroke Accumulator displaces cylinder rod volume

Power take-off system Hydraulic Motor Drain Port By-pass: Check valves Swagelok fittings Hydraulic subsystem waterproof housing

Power take-off system Power take-off systems conveniently contained within water proof boxes

Power take-off system Boxes mount to frame Frame mounts to top of buoy Easy to access and maintain

Power take-off system Permanent Magnet DC Motor: Operated mechanically to function as a generator Microcontroller: Logs system data from voltage and current sensors in 16 MB SD card

Power take-off system Waterproof microcontroller housing Power dissipates in 1500 Watt 1 ohm resistor

Power take-off system

SUB-SYSTEMS (HEAVE PLATE)

Heave plate

Heave plate Steel square tubing arranged into framework . Test fitting before final welding of sheet steel Supported from spar by connections of steel cables

Heave plate Sheet steel limits water flowing around steel frame Hydrodynamic damping “Added mass” effect Sheet steel welded to frame using plug and bead welds

Heave plate Use of four individual modules advantageous for transportation and storage Plug welds Bead welds

Heave plate Steel cable, clips, and thimbles Steel cable threads through eyelets welded on steel frame

Heave Plate

NEXT STAGE (TESTING)

Ocean testing Mooring site at depth of 100 feet

Ocean testing Lifting with crane Ring hoists mounted to bottom of buoy, and section of steel frame Allows for lifting and transportation

Ring Hoists Ocean testing Ring hoist selected due to ability to lift angled loads Capacity of 5,000 lbs each

Transporting WEC Ocean testing List with 1 Ton crane in EFL Placed onto trailer provided by EFL Tow trailer and WEC with a FORD F-550

Ocean testing UC Davis Bodega Bay Marine Laboratory

BML Crane BML Boat Ocean testing 3 Ton lifting capacity 15 foot boom span Drive trailer directly onto dock BML Boat Mussel Point Research Vessel Boat: 42 foot long, with winch system Specifically designed operate in demanding waters nearshore and offshore

Example of a Float Bag and 2,000 lbs Anchor Ocean testing 2,000 lbs Anchor Plan A: train axel (vendor not responding) Plan B: purchase scrap steel $0.15/lbs and cut and weld Plan C: purchase scrap steel $0.40/lbs and vendor will weld Float Bag Plastic bag filled with air Provided by BML Can float 3,000 lbs Will float anchor behind boat Image provided by BML: Example of a Float Bag and 2,000 lbs Anchor

Data and results Collect data and analyze power output Compile results Create a manuscript and instruction manual Upload the instruction manual onto team website Upload informational videos to website (x5) Submit final report to CITRIS Team website Project Wiki

References A Review of Wave Energy Converter Technology. Drew, B, Plummer, AR and Sahinaya, MN. s.l.: Department of Mechanical Engineering, University of Bath, Bath, UK. Frequently Asked Questions. US Energy Information Administration. [Online] US Department of Energy, July 9, 2012. [Cited: November 20, http://www.eia.gov/tools/faqs/faq.cfm?id=105&t=3. Department, Minerals Management. Technology White Paper on Wave Energy Potential on the U.S.Outer Continental Shelf. s.l. : U.S. Department of the Interior, 2006. Hydraulics: 2X72X1.25 DA HYD CYL Item# 9-7707-72 . Surplus Center. [Online] 2010. [Cited: 02 18, 2013.] http://www.surpluscenter.com/item.asp?item=9-7707 72&catname=hydraulic. McMaster- Carr Supply Company. Plastic Material Properties: More About Plastics. McMaster-Carr. [Online] 2012. http://www.mcmaster.com/#8574kac/=llhc8n. McMaster-Carr Supply Company. More About Steel Alloys. McMaster-Carr. [Online] 2010. http://www.mcmaster.com/#88645kac/=llhola. More About Aluminum and Aluminum Alloys. [Online] 2010. [Cited: 04 22, 2013.] http://www.mcmaster.com/#8975kac/=llhszc. NOAA. NOAA Marine Environmental Buoy Database. National Oceanic and Atmospheric Administration. [Online] http://www.nodc.noaa.gov/BUOY/.   NOAA Ocean Facts. National Oceanic and Atmospheric Administration. [Online] 2011 йил 17- November. [Cited: 2012 йил 10-November.] http://oceanservice.noaa.gov/facts/population.html. Surplus Center. Hydraulics: 4X96X2.25 DA HYD CYL HEAVY DUTY CROSSTUBE. Surplus Center. [Online] 2012. [Cited: 02 12, 2013.] Urethane Technologies Inc. Floating Devices Catalog. Denham Springs, Louisiana, USA : s.n. US Energy Information Administration. Annual Energy Outlook 2012- Renewable Energy Generating Capacity and Generation. Washington DC : US Department of Energy, 2012. US Energy Information Administration. The Electric Power Monthly with Data for August 2012. Washington DC : US Department of Energy, 2012. Willis, H. L., Welch, G. V., and Schrieber, R. R. Aging Power Delivery Infrastructures. New York : Marcel Dekker, Inc, 2001.

Thank you for the opportunity to present our project Thank you for the opportunity to present our project. We hope you found this information useful. If you have any questions or comments, please feel free to ask.